The goal of the proposed project is to examine sleep disturbances in female rape victims with posttraumatic stress disorder (PTSD). In addition, a secondary goal is to assess the amelioration of these sleep disturbances as a result of psychotherapy for PTSD. Volunteers for the study will be administered a battery of interviews and self-report measures which will be comprised of: (1) Clinician Administered PTSD Symptom Scale (CAPS), (2) Structured Clinical Interview for DSM-III-R and DSM-IV (SCID-IV), (3) PTSD Symptom Scale (PSS), (4) Beck Depression Inventory (BDI), and (5) Pittsburgh Sleep Quality Index (PSQI). In addition, physiological indices of sleep functioning will be obtained using ambulatory equipment (NightWatch) with or without polysomnography laboratory equipment. The first phase of the study will involve finishing ambulatory sleep data collection on 10 female rape victims with PTSD and 10 control female rape victims without PTSD. The two groups will be matched on age, and time of going to bed. The data collected will help delineate specific sleep disturbances that characterize PTSD. In addition, 5 female rape victims with PTSD and 5 female rape victims without PTSD will be assessed on both ambulatory and polysomnography equipment. This will help establish the validity of the ambulatory data against the polysomnography data. The second phase of the study will involve assessing an additional 5 female rape victim with PTSD on both ambulatory and polysomnography equipment. The 10 total female rape victims with PTSD who are assessed on both ambulatory and polysomnography equipment (5 in the first phase and 5 in the second phase) will then be followed up after psychotherapy and reassessed on both ambulatory and polysomnography to examine improvement in the sleep disturbances as a result of improvement in PTSD symptomatology. This study will use the same mechanism for recruiting subjects as an already funded study which is successfully in place. The pre-existing study is a treatment outcome study comparing two modalities of psychotherapy for rape related PTSD symptoms in female rape victims. Conducting the current project will have important implications in the study of the sleep architecture in PTSD. Also, the findings will have important implications in treating the sleep pathology that forms a major part of PTSD symptom spectrum.